Lunch box



FIG. 1 is a perspective view of the lunch box showing our new design;

FIG. 2 is a front view thereof, the rear view being identical to the front view;

FIG. 3 is a left side view thereof, the right side view being identical to the left side view:

FIG. 4 is a top view thereof; and,

FIG. 5 is a bottom view thereof. 

CLAIM The ornamental design for a lunch box, as shown and described. 